Old-port node detection and hub port bypass

1. A hub port in a Fibre Channel loop, comprising: a hub data source for supplying data to the hub port from the Fibre Channel loop; a detect circuit configured to detect a valid non-Arbitrated Loop sequence from an attached node port indicating that the node port is in a mode for operating in a non-Arbitrated loop environment, said valid non-Arbitrated Loop sequence comprising a first non-Arbitrated Loop sequence followed by at least two more consecutive non-Arbitrated Loop sequences substantially similar to the first sequence; and an output control circuit operating to bypass the node port from the loop when the valid non-Arbitrated Loop sequence is detected.

2. A hub port in a Fibre Channel loop, comprising: a hub data source for supplying data to the hub port from the Fibre Channel loop; a detect circuit configured to detect a valid non-Arbitrated Loop sequence from an attached node port indicating that the node port is in an OLD-PORT state; and an output control circuit operating to bypass the node port from the loop when the valid non-Arbitrated Loop sequence is detected, wherein said non-Arbitrated Loop sequence includes Link Reset (LR), Link Reset Response (LRR), Not Operational (NOS), and Offline (OLS) ordered sets.

3. A hub port in a Fibre Channel loop, comprising: a hub data source for supplying data to the hub port from the Fibre Channel loop; a detect circuit configured to detect a valid non-Arbitrated Loop sequence from an attached node port indicating that the node port is in an OLD-PORT state; and an output control circuit operating to bypass the node port from the loop when the valid non-Arbitrated Loop sequence is detected, wherein said detect circuit indicates detection of said valid non-Arbitrated Loop sequence if said detect circuit detects a first non-Arbitrated Loop sequence followed by at least two more consecutive non-Arbitrated Loop sequences substantially similar to the first sequence.

4. The hub port of claim 3 , further comprising: a memory configured to store the first detected non-Arbitrated Loop sequence.

5. The hub port of claim 3 , further comprising: a fill-word generator operating to generate and transmit fill-words in place of the detected non-Arbitrated Loop sequences.

6. The hub port of claim 5 , further comprising: a data selection device configured to selectively direct data from an appropriate data source to the Fibre Channel loop in accordance with a control signal from said output control circuit.

7. The hub port of claim 6 , wherein said appropriate data source includes the hub data source, the attached node port, and the fill-word generator.

8. The hub port of claim 1 , further comprising: a loop initialization sequence generator configured to generate a loop initialization sequence, where said sequence is sent to awake the attached node port when the node port is determined to be in an OLD-PORT state.

9. The hub port of claim 8 , wherein said detect circuit operates to detect a valid LIP primitive sequence from the attached node port, after the loop initialization sequence generator sends the loop initialization sequence.

10. A hub port in a Fibre Channel loop, comprising: a hub data source for supplying data to the hub port from the Fibre Channel loop; a detect circuit configured to detect a valid non-Arbitrated Loop sequence from an attached node port indicating that the node port is in an OLD-PORT state said valid non-Arbitrated Loop sequence comprising a first non-Arbitrated Loop sequence followed by at least two more consecutive non-Arbitrated Loop sequences substantially similar to the first sequence; an output control circuit operating to bypass the node port from the loop when the valid non-Arbitrated Loop sequence is detected; a fill-word generator operating to generate and transmit fill-words in place of the detected non-Arbitrated Loop sequences; and a data selection device configured to selectively direct data from an appropriaate data source to the Fibre Channel loop in accordance with a control signal from said output control circuit.

11. A Fibre Channel loop having a hub, comprising: a plurality of node ports; a plurality of hub ports in the hub, each hub port coupled to one of said plurality of node ports, each hub port including: a hub data source for supplying data to the hub port from the Fibre Channel loop; a detect circuit configured to detect a valid non-Arbitrated Loop sequence from an attached node port indicating that the node port is in an OLD-PORT state, said valid non-Arbitrated Loop sequence comprising a first non-Arbitrated Loop sequence followed by at least two more consecutive non-Arbitrated Loop sequences substantially similar to the first sequence; and an output control circuit operating to bypass the node port from the loop when the valid non-Arbitrated Loop sequence is detected.

12. A method for detecting and bypassing node ports in an OLD-PORT state, comprising: detecting a valid non-Arbitrated Loop sequence from a node port, said valid non-Arbitrated Loop sequence comprising a first non-Arbitrated Loop sequence followed by at least two more consecutive non-Arbitrated Loop sequences substantially similar to the first sequence; and appropriately bypassing the node port in response to detecting said valid non-Arbitrated Loop sequence.

13. The method of claim 12 , wherein said appropriately bypassing includes forwarding data received from previous hub port directly to next hub port.

14. A method for detecting and bypassing node ports in an OLD-PORT state, comprising: detecting a valid non-Arbitrated Loop sequence from a node port; and appropriately bypassing the node port, wherein said detecting said valid non-Arbitrated Loop sequence includes monitoring to detect at least three identical and consecutive Link Reset (LR), Link Reset Response (LRR), Not Operational (NOS), or Offline (OLS) ordered sets.

15. A method for detecting and bypassing node ports in an OLD-PORT state, comprising: detecting a valid non-Arbitrated Loop sequence from a node port; and appropriately bypassing the node port; and generating and transmitting a loop initialization sequence to awake the node port in the OLD-PORT state.

16. The method of claim 15 , further comprising: cutting the node port into the Fibre Channel loop if a valid LIP sequence is received from the node port.

17. The method of claim 16 , wherein said cutting in includes re-attaching the bypassed node port into the Fibre Channel loop.

18. A method for detecting and bypassing node ports in an OLD-PORT state, comprising: detecting a valid non-Arbitrated Loop sequence from a node port, said valid non-Arbitrated Loop sequence comprising a first non-Arbitrated Loop sequence followed by at least two more consecutive non-Arbitrated Loop sequences substantially similar to the first sequence; appropriately bypassing the node port in response to said detecting; generating and transmitting a loop initialization sequence to awake the node port in the OLD-PORT state; and cutting the node port into the Fibre Channel loop if a valid LIP sequence is received from the node port.

19. An apparatus comprising a machine-readable storage medium having executable instructions that enable the machine to: detect a valid non-Arbitrated Loop sequence from a node port, said valid non-Arbitrated Loop sequence comprising a first non-Arbitrated Loop sequence followed by at least two more consecutive non-Arbitrated Loop sequences substantially similar to the first sequence; and appropriately bypass the node port in response to said detecting.

20. An apparatus comprising a machine-readable storage medium having executable instructions that enable the machine to: detect a valid non-Arbitrated Loop sequence from a node port; appropriately bypass the node port; generate and transmit a loop initialization sequence to awake the node port in the OLD-PORT state; and cut the node port into the Fibre Channel loop if a valid LIP sequence is received from the node port.